[v3,7/8] i2c: designware: Add debug print for SDA hold time value

Message ID 20180611142248.10798-8-jarkko.nikula@linux.intel.com
State New
Headers show
Series
  • i2c: designware: Improve debug prints
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Commit Message

Jarkko Nikula June 11, 2018, 2:22 p.m.
SDA hold time is an important timing parameter and often reason for
arbitration lost errors if not set to a correct value. Add a debug print
for it in order to see what value gets programmed to a HW.

Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
---
 drivers/i2c/busses/i2c-designware-common.c | 4 ++++
 1 file changed, 4 insertions(+)

Patch

diff --git a/drivers/i2c/busses/i2c-designware-common.c b/drivers/i2c/busses/i2c-designware-common.c
index e3ae9159a822..2faa09711aee 100644
--- a/drivers/i2c/busses/i2c-designware-common.c
+++ b/drivers/i2c/busses/i2c-designware-common.c
@@ -209,6 +209,10 @@  int i2c_dw_set_sda_hold(struct dw_i2c_dev *dev)
 		 */
 		if (!(dev->sda_hold_time & DW_IC_SDA_HOLD_RX_MASK))
 			dev->sda_hold_time |= 1 << DW_IC_SDA_HOLD_RX_SHIFT;
+
+		dev_dbg(dev->dev, "SDA Hold Time TX:RX = %d:%d\n",
+			dev->sda_hold_time & ~(u32)DW_IC_SDA_HOLD_RX_MASK,
+			dev->sda_hold_time >> DW_IC_SDA_HOLD_RX_SHIFT);
 	} else if (dev->sda_hold_time) {
 		dev_warn(dev->dev,
 			"Hardware too old to adjust SDA hold time.\n");